Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what estimate his Department has made of the total of nuclear warheads deployed by (a) Russia, (b) China, (c) the US and (d) France on (i) intercontinental and (ii) intermediate-range missiles in each of the last five years.

The Ministry of Defence continues to track the threat from nuclear and advanced novel weapons systems held by potential adversaries. Our estimates of our adversaries' nuclear warhead stockpiles remains classified. We judge that Russian strategic and intermediate nuclear capabilities continue to grow, both in terms of warheads and delivery systems. Figures declared by Russia under the New START Treaty do not provide an accurate picture of the growth in the nuclear threat that Russia presents. China does not declare its nuclear warhead numbers but is currently undertaking a significant modernisation programme with an expansion of its nuclear arsenal and development of a nuclear triad. Both countries are also investing heavily in novel weapons systems.